Method of producing novelty yarn and apparatus associated therewith



y 25, 1967 YASUJI NAKAHARA- 3,333,040

METHOD OF PRODUCING NOVELTY YARN AND APPARATUS ASSOCIATED THEREWITH'Filed Dec. 2, 1963 United States Patent 3,333,040 METHOD OF PRODUCINGNOVELTY YARN AND APPARATUS ASSOCIATED THEREWITH Yasuji Nakahara,Nobeoka-shi, Japan, assignor to Asahi Kasei Kogyo Kabushiki Kaisha,Osaka, Japan, a corporation of Japan Filed Dec. 2, 1963, Ser. No.327,286 Claims priority, application Japan, Dec. 17, 1962, 37/55,393 14Claims. (Cl. 264-164) This invention relates to the manufacture ofnovelty yarn, and in particular to a method for the manufacture ofnovelty yarn comprising continuous filaments, which yarn can be madeinto fabric having a novel effect such as knotty shantung fabric. Thereis known a method for producing fancy yarns by spinning, which methoduses running water as a stretching medium, such as the spinning of rayonand the like, which is disclosed in U.S.P. 2,251,247. It is a stretchspinning method for producing yarn with irregular knots and ischaracterized by sufiiciently coagulating one of two separated spinningyarns of filaments by normal condition (this filament yarn is referredto as strength yarn hereinafter), coagulating the other yarn in a bathcontaining an increased amount of coagulation liquid or in a bathmaintained at a low temperature and combining these two filaments intoone yarn in a regenerating bath while causing the latter yarn to strikea receiver installed under a funnel (this filament yarn is referred toas slouched yarn hereinafter). However in this method, the differencesin the spinning conditions of the strength yarn and the slouched yarn(an amount and temperature of coagulation liquid), requires that thedifference in the coagulation state of the two yarns in the spinningprocess be made fairly large. The filament produced by such a methodfrequently causes problems in the weaving process, and in the handlingof fabrics made from said filament. There is no doubt that spinning yarnby one set of apparatus having two different spinning conditions iscommercially unfavorable.

If, in this instance, the spinning conditions between the strength yarnand the slouched yarn could be made equal, there would be provided acommercially advantageous spinning method Moreover, since filament yarnsof almost the same coagulation state are combined in this method, itwould produce knotty yarns of superior properties.

After an extensive and careful study of the spinning process which usesrunning water as a stretching medium, I have now solved theabove-described drawback.

Observing the spinning process which utilizes running water as astretching medium, it is seen that the coagulation liquid delivered intoa coagulation funnel flows from the-outlet of said funnel whilepromoting coagulation of the spinning solution and stretching it toshape filaments by means of the friction between the filament yarn andthe liquid. At the ordinary spinning, or at the spinning of the strengthyarn, the speed of the filament yarn given 'by the drawing and thestretching of this coagulation liquid before being taken up by thewinder must be equal to or slower than the take-up speed.

The first point which should be noted is that the speed of thecoagulation bath from the outlet of the funnel can be increased by theacceleration of gravity to such an extent as to cause the speed of theyarns before being taken up to be greater than take-up speed undernormal spinning conditions as described above. In other words, if thelength of the free fall of the coagulation liquid is increasedsufiiciently, the falling speed of the coagulation liquid due togravitational acceleration becomes so large, that the filament yarn issufliciently stretched, as a result of which the speed of the filamentyarn before being taken up can be made greater than the take-up3,333,040 Patented July 25, 1967 ice speed. Therefore it becomespossible to take-up the yarn while forming irregular knots. In otherwords, it is pos sible to form the slouched yarn by making the filamentyarn together with coagulation liquid strike a receiver installedbeneath the spinning funnel, permitting it to remain there momentarily,thereby forming entanglements or loops while in a state of insufiicientcoagulation.

The second point which should be noted is that the speed of thecoagulation liquid which is being accelerated by free fall i interruptedor reduced half way, thereby controlling the falling speed of thefilament. It is preferable to install a lower step funnel, i.e. a smallsized coagulation bath as hereinafter described, and promote theultimate coagulation by which the speed-increase of the filament yarndue to drawing can be controlled at a moderate value and thus a strengthyarn can be spun.-

For example, when a small sized funnel having a broad opening on the topis inserted as the lower step funnel in the path of the falling filamentyarn, the coagulation liquid fills this low step funnel and falls downfrom the bottom hole of this funnel together with filament yarn, bywhich the speed of coagulation liquid in the free falling part isinterrupted and reduced.

This invention is based upon the above-described findings. The detailsof the present method will be more fully described by reference to theaccompanying schematic drawing.

In the drawing, coagulation liquid is delivered from inlet pipes 1 and 1through stream regulators 2 and 2 and, simultaneously, spinning solutionis extruded from spinnerets 3 and 3 and formed into filament yarns whileundergoing drawing and coagulation in spinning funnels 4 and 4'. Bothspinning funnels are the same, and the spinning conditions withinfunnels 4 and 4 are also the same. The coagulation liquid dischargedfrom spinning funnel 4 increases its falling speed by gravitationalacceleration during its sufficiently long free falling distance 6 whilestretching the spun filament yarn and strikes at receiver 7 placed inthe path of the falling filament yarn. This receiver can be either adish, a fiat plate, or an uneven plate. Its angle of inclination can befreely selected. In this instance, the distance between funnel 4 andreceiver 7 (i.e. free falling length) can be determined according to thespinning condition. Accordingly when the filament speed is suflicientlylarger than the take-up speed, the falling filament yarn strikesreceiver 7, remains there momentarily and forms loops or entanglementsin a premature state of coagulation. Thus it is taken up as slouchedyarn.

The coagulation liquid discharged from the other spinning funnel 4'enters the small sized lower step funnel 8 located halfway through itsfree fall distance, its falling speed is interrupted, thereby drawing aswell as stretching, and the falling speed of filament yarn 9 issuppressed. The filament yarn subsequently passes direction changing rod10, :and is combined as a strength yarn with the above describedslouched yarn and regenerated in bath 11, by which novelty yarns havingirregular knots can be produced.

It will be favorable to provide the lower step funnel with a suitablebuffer bath which controls the free falling of the coagulation liquidand does not damage the filament yarn. Its location, length and shapemay vary according to spinning conditions such as temperature and amountof spinning liquid, desired denier of yarn to be produced, diameter ofthe spinning nozzle, etc., but it will be favorable to arrange it sothat the tension of the filament yarn before being taken up is at amaximum. It is also possible to use a multiple funnel, i.e. one in whichtwo or more funnels are assembled into a set.

As is obvious from the above description, the present method is not onlycommercially advantageous in that it 3 enables one to spin knotty yarnsby use of the same amount of spinning liquid, the same temperature ofcoagulation bath and the same spinning funnel, but also in that itproduces novelty yarns having superior properties.

The invention will be better understood by describing it in connectionwith the following specific example of the practice of it, in whichproportions are expressed as percent by weight.

Example As is shown in the accompanying drawing, normal stretch spinningfunnels, as used in the cuprammonium process, having 40 cm. length and0.4 cm. outlet diameter are used. Under funnel 4', lower step funnel 8as described above having 10 cm. length, and 0.25 cm. outlet diameter isplaced at a distance of cm. from the lower end of the funnel 4. At adistance of cm. from the top of lower step funnel 8 is placed directionchanging rod 10. Under funnel 4, receiver 7 having 0.5 cm. depth and 7cm. width is placed at a distance of 40 cm. from the lower end of funnel4. A spinning solution containing 9 percent cellulose, 7.2 percentammonia, and 3.7 percent copper is extruded from spinnerets 3 and 3'each having 54 holes of 0.8 mm. diameter, after which it is coagulatedwhile stretching by use of 800 cc./min. of water at a temperature of 28C., combined into one yarn in regenerating bath 11 of 6.5 percentsulfuric acid and taken up by hanks at a take-up speed of 65 m./min. asmultifilamentof mean 150 denier.

In this instance the filament yarn 9, spun by funnel 4' enters the lowerstep funnel 8 which is always kept filled with down pouring water and byits buffer action, stretch-- ing of the filament is suppressed, whilepromoting coagulation and the take-up of the filament yarn is performedas usual. On the other hand, the filament yarn, spun by.

obtained by a known method (U.S.P. 2,251,247), the

former shows superior properties in weaving operations.

When yarns made by the known method are rewound from reels to bobbins,there are countedlOO to 300 cuts per 100,000 meters of yarn, whereas theyarn made according to the method described in this specific examplereveals only 3 to 4 cuts per 100,000 meters of yarn.

What I claim is:

1. A method for producing a novelty yarn having ir-' regularly spacedknots, said method comprising simultaneously extruding two separatespaced filaments of the same size and composition at a common level suchthat the filaments freely fall in space vertically, combining thefilaments after one has fallen a greater distance than the other andreducing the speed of fall of the filament which passes through thelesser distance.

2. A method as claimed in claim 1 wherein the speed is reduced bypassing the filament through a buffer bath.

3. A method as claimed in claim 2 wherein the buffer bath is placedabout midway through the distance through which the filament falls.

4. A method as claimed in claim 1 comprising interrupting the fall ofthe filament which has fallen the greater distance and causing the sameto momentarily accumulate whereby knots are formed therein beforecombination with the other filament.

5. A method for producing a novelty yarnhaving irregularly spaced knots,said method comprising the steps of simultaneously extruding at leasttwo separate filaments from a coagulable solution through acorresponding number of spinning funnels, discharging said filaments ina partially coagulated state from said spinning funnels, allowing saidpartially coagulated filaments to freely fall and acquire free fallvelocities, whereby said partially coagulated filaments form yarns, oneof said partially coagulated filaments being allowed to fall a greaterdistance than the other of said partially coagulated filaments tostretch said one partially coagulated filament, interrupting the fall ofthe thusly stretched partially coagulated filament while momentarilycausing the same to accumulate whereby a slouched yarn is formed;passing the other of said partially coagulated filaments through a lowerstep funnel containing a buffer bath during its free fall to cause saidother partially coagulated filament to fallwith reduced velocity,whereby a strength yarn is formed, combining the thusly formed strengthyarn with the slouched yarn while advancing the two formed yarnstogether at.

a velocity which is less than the free fall velocity of the said onepartially coagulated filament, and greater than the reduced velocity ofsaid other partially coagulated filament, and subjecting the thuslycombined yarn to the action of a regenerating bath.

6. A method as claimed in claim 5 wherein said coagu lable solutioncomprises cellulose derivatives.

. 7. A method as claimed in claim 5 wherein said coagulable solutioncomprises cuprammonium.

8. A method as claimed in claim 5 wherein said regen erating bathcomprises sulfuric acid.

9. Apparatus for producing novelty yarn comprising.

first and second vertical spinning funnels in horizontally spacedrelation and having outlets at a common horizontal level, means forsupplying separate streams of spinning transporting the same at a speedsuch that irregular knotsare formed in the filament yarnwhich contactssaid receiver while the other yarn is stretched.

10. An apparatus as claimed in claim 9 wherein the outlets are of equaldiameter.

11. An apparatus as claimed in claim 9 wherein the spinnerets are eachprovided with an equal number of perforations of uniform diameter.

12. An apparatus as claimed in claim 9 wherein the receiver is a shallowdish.

13. An apparatus as claimed in claim 12 wherein the dish has an unevensurface.

14. An apparatus as claimed in claim 9 wherein the means for reducingthe speed of free fall is a lower step funnel containing a buffer bath.

References Cited:

UNITED STATES PATENTS 1,933,607 11/1933 Taylor 156-167 2,041,798 5/1936Taylor 156-467 2,182,429 12/1939 Frowein et al 156167 2,251,247 7/1941Bauriedel et al. 156-167 2,730,757 1/1956 Holfman 156167 ALEXANDER H.BRODMERKEL, Primary Examiner. J. WOO, Assistant Examiner.

1. A METHOD FOR PRODUCING A NOVELTY YARN HAVING IRREGULARLY SPACEDKNOTS, SAID METHOD COMPRISING SIMULTANEOUSLY EXTRUDING TWO SEPARATESPACED FILAMENTS OF THE SAME SIZE AND COMPOSITION AT A COMMON LEVEL SUCHTHAT THE FILAMENTS FREELY FALL IN SPACE VERTICALLY, COMBINING THEFILAMENTS AFTER ONE HAS FALLEN A GREATER DISTANCE THAN THE OTHER ANDREDUCING THE SPEED OF FALL OF THE FILAMENT WHICH PASSES THROUGH THELESSER DISTANCE.